98 12v misfiring
 

My 98 fires up fine, after driving has a bad miss. I can drain the water separator and it will level out. Once I drive again it's back to the same thing. I've changed the filter, took fuel sample and no water or debris. Recently have put in new 50hp injectors, overflow valve, pre-heater delete. It could be coincidence but it seems like it started this problem after I changed the OFV. Need help on what else the issue might be. Any advice appreciated.

If you have a temp-gun, you might be able to see if you have a dead cylinder or at least one with low temp. That may indicate a failing/ failed injector issue. What is your fuel pressure?

Thanks for the reply. Turns out the new OFV I got was bad. I decided to put the old one back on to see if that might make any difference and it fixed the problem. Fuel pressure went straight to 20 at idle after putting old one back on. With the bad new one was only getting 10 at idle.

Wow, good catch! I would have missed that especially with a new OFV. Enjoy........:tu: